Dietary guidelines have been established for the treatment of hypertension and for the prevention of cardiovascular disease, but there are no dietary guidelines to prevent kidney disease, a condition that affects about 31 million people in the U.S.
“Dietary guidelines exist for people with active kidney disease, but there are no diet recommendations for preventing kidney disease,” Kevin Longino, CEO of the National Kidney Foundation and a kidney patient himself, said in a press release. “This new study suggests a novel approach in helping to prevent kidney disease.”
Two of the leading causes of kidney disease are high blood pressure and diabetes, which can often be traced to dietary factors.
DASH is a diet pattern designed primarily to reduce high blood pressure. The diet has also shown to be effective in preventing a number of chronic conditions like cardiovascular disease, diabetes, stroke, and some forms of cancers. The DASH diet emphasizes eating more fresh fruits and vegetables, whole grains, legumes, fat-free or low-fat dairy, and less red and processed meat, sugar-laden beverages and sodium (salt).
Casey M. Rebholz of Johns Hopkins Bloomberg School of Public Health and colleagues examined data from the Atherosclerosis Risk in Communities (ARIC) Study conducted between 1987 and 2013.
The study included 14,882 participants (ages 45 to 64) enrolled from four areas in the U.S: Jackson, Mississippi; Forsyth County, North Carolina; suburbs of Minneapolis, Minnesota; and Washington County, Maryland. Participants were not advised to follow a DASH diet, but their diets were analyzed to see how closely they matched it during the normal course of their lives.
During a median follow-up of 23 years, 3,720 participants developed kidney disease.
Participants with a DASH diet score in the lowest percentile were 16 percent more likely to develop kidney disease than those with the highest score, after adjusting for variables such as sociodemographics, smoking status, physical activity, total caloric intake, baseline eGFR, overweight/obese status, diabetes status, hypertension status, systolic blood pressure, and antihypertensive medication use.
Of the individual components of the DASH diet score, high red and processed meat intake was adversely associated with kidney disease, and high intake of nuts, legumes, and low-fat dairy products was associated with reduced risk for kidney disease.
“I was surprised and encouraged by the robustness of the findings as relatively little is known about healthy dietary patterns for reducing the risk of kidney disease. If we are able to modify dietary intake, there is great potential for reducing the costly societal and individual burden of kidney disease in the U.S. population,” Rebholz said.
“The main message is the same for healthcare professionals and the general population: The DASH diet, which is widely recommended for reducing blood pressure and the risk of cardiovascular and other chronic conditions, may also protect against kidney disease for generally healthy individuals,” Rebholz added.
Currently available guidelines for people with kidney disease recommend a reduction of dietary protein intake. However, they do not differentiate between types of protein.